CN102717408B - Bamboo and wood composite container bottom plate manufactured by one-step hot pressing and having high elastic modulus and manufacture method thereof - Google Patents

Abstract

The present invention is a high elastic modulus bamboo-wood composite container bottom plate formed by one-time hot pressing and its manufacturing method. layer veneer, and then inwards is particle board for structure; or use wooden veneer inward; or replace the vertical and horizontal wooden veneers with some bamboo curtains; the number of layers and fiber directions of wooden veneers or bamboo curtains are according to The structural principle of the container floor is determined. Advantages: Utilize the most compacted bamboo curtain surface layer with high elastic modulus, so that the elastic modulus of the bottom plate is greatly improved, with less energy consumption, and the surface bamboo curtain has low water absorption expansion rate, high hardness and good wear resistance The characteristics of the bottom plate broaden the raw material source of the bottom plate, and the quality of the composite container bottom plate is stable, and its strength, elastic modulus and other performance indicators meet the technical requirements of the international container industry.

Description

High elastic modulus bamboo-wood composite container bottom plate formed by one-time hot pressing and its manufacturing method

technical field

The invention relates to a bamboo-wood composite container floor with a high elastic modulus formed by one-time hot pressing with multi-layer bamboo curtains as the surface layer and a manufacturing method thereof, which belongs to the technical field of wood-based panel manufacturing in the wood industry.

Background technique

The main load-bearing area of a container is the bottom plate. The container manufacturing industry requires the bottom plate to have high mechanical properties, appearance quality, impact resistance and aging resistance. The existing bamboo-wood composite container floor has two forms: the surface layer of patent ZL 98111153.x is a kind of bamboo-wood composite container floor with impregnated paper and bamboo mat, and the surface layer of another patent ZL 03152841.4 is formed by high-pressure hot pressing A thin layer of high-density bamboo is used as the surface and back layer, and then combined with structural particleboard or poplar veneer as the core for a second heat press. The first type needs to impregnate paper and bamboo mats in order to obtain a beautiful appearance. Bamboo mats require more labor costs, and the elastic modulus of the bottom plate is not high; the latter type can also achieve the required mechanical properties and acceptable appearance. , but because of the secondary molding, it is necessary to sand the surface to be glued and apply glue, and then go through secondary hot pressing and compounding, which consumes more energy, materials and labor. These two kinds of bamboo-wood composite container bottom plates have high cost, which is difficult for container owners to accept. Therefore, the present invention uses a special bamboo screen to obtain the required surface quality in one molding process, and the high elastic mold that is difficult to achieve for conventional bamboo-wood composite container bottom plates. quantity. It has the characteristics of saving materials, less energy consumption, wear resistance, etc., and can use sustainable domestic bamboo wood with rich resources to produce container floor, which broadens the source of floor materials and has far-reaching practical significance.

Contents of the invention

The object of the present invention is to provide a bamboo-wood composite container bottom plate with multi-layer high elastic modulus bamboo curtain as the surface layer and its manufacturing method. The present invention utilizes the top layer of compacted bamboo curtain surface layer with high elastic modulus. The high elastic modulus of this layer contributes the most to the elastic modulus of the bottom plate, so that the elastic modulus of the bottom plate can be greatly improved, and the surface layer Bamboo curtain has the characteristics of low water expansion rate, high hardness and good wear resistance. The core layer can use structural particleboard, wood veneer, bamboo curtain and other materials with high shear resistance, which can be used alone or in combination. In order to make the surface beautiful, a layer of thin veneer, or phenolic impregnated paper, or phenolic impregnated glass fiber cloth can be pasted on the outer layer of the surface bamboo curtain.

The technical solution of the present invention: a high elastic modulus bamboo-wood composite container bottom plate is formed by one-time hot pressing, which is characterized in that the upper and lower layer materials adopt a layer of thin bamboo curtain with longitudinal texture, 2 to 4 layers of bamboo curtain with longitudinal texture and a layer of transverse texture Wooden veneer; upper and lower layer material A facing inward is a structural particle core board; or upper and lower layer material A facing inward uses longitudinal grain wood veneer and multi-layer wood veneer, a total of 11 layers of wood veneer, the middle three The layers are all longitudinal grain veneers, and the rest of the veneers are laid according to a longitudinal grain veneer and a transverse grain veneer.

A manufacturing method of high modulus of elasticity bamboo-wood composite container bottom plate formed by one-time hot pressing, the process steps are divided into:

a. Sorting and finishing of wooden veneers and bamboo curtains. The moisture content of wooden veneers is ≤10%. According to the required double-sided glue coating, the amount of glue applied is 250-350g/m ² , aged or dried at low temperature; Bamboo curtains of different varieties are dried to below 12% moisture content, then dried at low temperature to below 20% moisture content by impregnating phenolic glue (or melamine glue), adding insecticide to the glue;

b. Particleboard core board for structure, the thickness of the particleboard substrate for structure is sanded to 20-22mm, and then used as the core board;

C. Blank assembly, use wood veneer, bamboo curtain and other materials alone or in combination, or assemble bamboo curtain, veneer and particleboard core board for structure, at a temperature of 125-150°C and a maximum pressure of 2.0-4.0 Carry out hot pressing under the condition of MPa, keep it for 8-35 minutes, then pass cold water into the hot pressing plate, and release the pressure after the hot pressing plate cools down to a certain temperature.

Advantages of the present invention: it can effectively utilize woods of different tree species and different diameters in my country and all over the world, such as various coniferous and broad-leaved woods in natural forests and artificial forests, and have fast growth, short cycle, annual Bamboo resources that can be selectively cut and used for a long time. Using these materials alone or in combination, through scientific design and reasonable combination, can not only solve the difficulty of hardwood shortage in the world, but also solve the technical problem of mass production of new bottom plates that meet the technical requirements of the international container industry. Use 6-12 layers of thin bamboo curtains with high elastic modulus impregnated with phenolic glue as the surface and back layer materials, a layer of horizontal veneer inward, and a special structural particleboard inward; or all wooden veneers inward ; or replace the vertical and horizontal wooden veneers with some bamboo curtains, and insecticides should be added to the glue used to make it evenly penetrate into the surface material of the container floor during hot pressing, so that the floor has long-term insect-proof performance; The core layer material and the surface layer material are combined into a slab, and then hot-pressed and glued to form a container bottom plate. Its strength, elastic modulus and other performance indicators can fully meet the technical requirements of the international container industry.

Description of drawings

Accompanying drawing 1 is the structural schematic diagram of the first high-elastic-modulus bamboo-wood composite container floor formed by one-time thermocompression.

Accompanying drawing 2 is the structural schematic diagram of the second high elastic modulus bamboo-wood composite container floor formed by one-time hot pressing.

Accompanying drawing 3 is the structural schematic diagram of the third kind of high elastic modulus bamboo-wood composite container floor formed by one-time hot pressing.

In the figure: 1 is the thin bamboo curtain with longitudinal texture, the upper and lower layers of the thin bamboo curtain with longitudinal texture are impregnated with phenolic glue (or melamine glue) and dried at low temperature; 2 is the bamboo curtain with longitudinal texture A, the bamboo curtain with longitudinal texture is impregnated Phenolic glue (or melamine glue) and dried at low temperature, its thickness is 1.0 ~ 1.8mm; 3 is the horizontal grain wood veneer, the horizontal grain wood veneer is double-sided coated or impregnated with phenolic glue and dried at low temperature; 4 is the structure Particle board core board is used; 5 is a longitudinal grain wooden veneer; 6 is a horizontal grain bamboo curtain, one layer of which is impregnated with phenolic glue and dried at low temperature; 7 is B longitudinal grained bamboo curtain, one layer of which is impregnated with phenolic glue and dried at low temperature; 8 is a multilayer wooden veneer; 9 is a multilayer wooden veneer and a bamboo curtain.

Detailed ways

With reference to accompanying drawing 1, its structure is that the surface layer and the bottom layer of the particle board core board 4 for structure are horizontal grain wood veneer 3, and the surface layer of transverse grain wood veneer 3 and the bottom surface layer of horizontal grain wood veneer 3 that are arranged symmetrically with it It is three layers of A vertical texture bamboo curtain 2, and on the top layer of A vertical texture bamboo curtain 2 and the bottom surface layer of the bamboo curtain 2 that is symmetrically arranged with it, is vertical texture thin bamboo curtain 1.

With reference to accompanying drawing 2, its structure is that the surface layer and the bottom layer of multi-layer veneer 8 are longitudinal grain wood veneer 5, and the surface layer of longitudinal grain wood veneer 5 and the bottom layer of the longitudinal grain wood veneer 5 that is arranged symmetrically with it are horizontal grain wood veneer 5. The veneer 3, the surface layer of the transverse grain wooden veneer 3 and the bottom layer of the transverse grain wooden veneer 3 symmetrically arranged are three layers of longitudinal grain bamboo curtains 2 and longitudinal grain thin bamboo curtains 1 in sequence.

With reference to accompanying drawing 3, its structure is that the top layer and the bottom layer of multi-layer wooden veneer and bamboo screen 9 are B vertical grain bamboo screen 7, the top layer of B vertical grain bamboo screen 7 and the bottom layer of B vertical grain bamboo screen 7 that are symmetrically arranged with it It is a horizontal texture bamboo curtain 6, the top layer of the horizontal texture bamboo curtain 6 and the bottom layer of the horizontal texture bamboo curtain 6 arranged symmetrically with it is a longitudinal texture wooden veneer 5, the surface layer of the longitudinal texture wooden veneer 5 and the longitudinal texture wooden veneer symmetrically arranged therewith. The bottom layer of the veneer 5 is a horizontal texture wooden veneer 3, and the top layer of the horizontal texture wooden veneer 3 and the bottom layer of the horizontal texture wooden veneer 3 symmetrically arranged with it are four layers of A longitudinal texture bamboo curtains 2.

The upper and lower layers of the thin bamboo curtain 1 with longitudinal texture are impregnated with phenolic glue and dried at low temperature; 3 double-sided coating or impregnated with phenolic glue and dried at low temperature; longitudinal texture wooden veneer 5 is a layer of dried veneer; horizontal textured bamboo curtain 6 one layer is impregnated with phenolic glue and dried at low temperature; B longitudinal textured bamboo curtain 7 is a layer of phenolic glue impregnated and dried at low temperature; the veneer in the multilayer wooden veneer 8 is a layer of coated phenolic glue and a layer of non-glue alternately; the bamboo curtain in the multilayer wooden veneer and bamboo curtain 9 It is impregnated with phenolic glue and dried at low temperature. When the veneers in the multi-layer wooden veneer and bamboo screen 9 are connected with the veneer, only one of the contact surfaces can be coated with phenolic glue. Coat the phenolic glue on the veneer.

Example 1:

The structure of the bamboo-wood composite container floor is shown in Figure 1.

The manufacturing method of the bamboo-wood composite container bottom plate is as follows:

a. Sorting and finishing of wooden veneers and bamboo curtains. The moisture content of wooden veneers is ≤10%. According to the required double-sided glue coating, the amount of glue applied is 250-350g/m ² , aged or dried at low temperature; and the longitudinal grain The thin bamboo curtain 1 and the vertical texture bamboo curtain 2 are dried to a moisture content below 12%, and then dried at low temperature to a moisture content below 18% by impregnating phenolic glue (or melamine glue). Add 2.4 grams of pesticides;

b. Particleboard core board for structure, the thickness of the particleboard substrate for structure is sanded to 20-22mm, and then used as the core board;

C. Blank assembly, from outside to inside: 1 layer of thin bamboo curtain with vertical texture impregnated with phenolic glue and dried at low temperature 1, three layers of bamboo curtain with longitudinal texture impregnated with phenolic glue and dried at low temperature with a thickness of 1.0-1.8mm 2, followed by a layer of double-sided coated (or impregnated) phenolic glue and dried at low temperature with a horizontal grain wood veneer 3, in the middle is 4 sets of core boards for structural particle boards. Carry out hot pressing at a temperature of 125-150°C and a maximum pressure of 2.5-4.0 MPa, keep it for 10-15 minutes, then pass cold water into the hot-pressing plate, and release the pressure after the hot-pressing plate cools to a certain temperature. After conventional post-processing, the finished composite container floor can be obtained, and its physical and mechanical properties are as follows:

MOR//: ≥95MPa

MOR⊥: ≥35MPa

MOE//: ≥12000MPa

MOE⊥: ≥3500MPa

Density: 0.75～0.90g/cm ³ .

Example 2:

The structure of the bamboo-wood composite container floor is shown in Figure 2.

The manufacturing method of the bamboo-wood composite container bottom plate is as follows:

a. Sorting and finishing of wooden veneers and bamboo curtains. The moisture content of wooden veneers is ≤8%. Glue is applied on both sides according to the requirements, and the amount of glue applied is 250-350g/m ² , aged or dried at low temperature; and the longitudinal grain The thin bamboo curtain 1 and the vertical texture bamboo curtain 2 are dried to a moisture content below 15%, and then dried at a low temperature to a moisture content below 20% after impregnating phenolic glue (or other weather-resistant glue), and the glue is 1 kg of glue (solid content 45%) Add 2.4 grams of insecticide;

b. Blank assembly, from the outside to the inside: 1 layer of thin bamboo curtain with longitudinal texture impregnated with phenolic glue and dried at low temperature 1, 3 to 4 layers of bamboo impregnated with phenolic glue and dried at low temperature with a thickness of 1.0 to 1.5 mm. The curtain 2 has 11 layers of wooden veneers facing inward, the three middlemost layers are all longitudinal grain veneers, and the rest of the veneers are laid according to a longitudinal grain veneer and a horizontal grain veneer. Then carry out hot pressing at a temperature of 125-150°C and a maximum pressure of 2.0-3.5MPa, keep for 30-35 minutes, then pass cold water into the hot-pressing plate, and release the pressure after the hot-pressing plate is cooled to 70°C.

After conventional post-processing, the finished composite container floor can be obtained, and its physical and mechanical properties are as follows: MOR//: ≥100MPa

MOR⊥: ≥35MPa

MOE//: ≥12000MPa

MOE⊥: ≥3500MPa

Density: 0.70～0.90g/cm ³ .

Example 3,

The structure of the bamboo-wood composite container floor is shown in Figure 3.

The manufacturing method of the bamboo-wood composite container bottom plate is as follows:

a. Sorting and finishing of wooden veneers and bamboo curtains. The moisture content of wooden veneers is ≤8%. Glue is applied on both sides according to the requirements, and the amount of glue applied is 250-350g/m ² , aged or dried at low temperature; and the longitudinal grain Bamboo curtain 2, bamboo curtain 6 with transverse texture and bamboo curtain 7 with vertical texture are dried to less than 12% moisture content, and then dried at low temperature to less than 20% moisture content through impregnating phenolic glue (or melamine glue). 45%) add 2.4 grams of pesticides;

b. Blank assembly, from the outside to the inside: 3 to 5 layers of phenolic glue impregnated and dried at low temperature with a thickness of 1.0 to 1.5mm. Longitudinal grain bamboo curtain 2, 11 layers of wooden veneer or bamboo curtain inward, the middle The three layers of bamboo curtains are all longitudinal grains, and the rest of the veneers or bamboo curtains are laid according to a longitudinal grain and a transverse grain. Then carry out hot pressing at a temperature of 135-150°C and a maximum pressure of 2.0-4.0 MPa, keep it for 30-35 minutes, then pass cold water into the hot-pressing plate, and release the pressure after the hot-pressing plate cools to a certain temperature.

After conventional post-processing, the finished composite container floor can be obtained, and its physical and mechanical properties are as follows: MOR//: ≥95MPa

MOR⊥: ≥35MPa

MOE//: ≥11500MPa

MOE⊥: ≥3500MPa

Density: 0.75～0.90g/cm ³ .

Claims (3)

1. A high elastic modulus bamboo-wood composite container bottom plate is formed by one-time hot pressing, which is characterized in that the upper and lower layers are made of a layer of thin bamboo curtain with longitudinal texture (1), 2-4 layers of bamboo curtain with longitudinal texture (2) and a layer of Wooden veneer with transverse grain (3); wood veneer with longitudinal grain (5) and multi-layer wood veneer (8 ), a total of 11 layers of wooden veneers, the middle three layers are all vertical grain veneers, and the rest of the veneers are laid according to a vertical grain veneer and a horizontal grain veneer. 2. According to claim 1, one-time thermoforming of high elastic modulus bamboo-wood composite container bottom plate is characterized in that the upper and lower layers are made of 3-5 layers of A longitudinal grain bamboo curtain (2) and a layer of transverse grain wood single Board (3), the upper and lower layer materials are inwardly replaced with horizontal textured bamboo curtain (6) and B longitudinal textured bamboo curtain (7) to replace vertical grained wooden veneer (5) and horizontal grained wooden veneer (3), a total of 11 layers Wooden veneer or bamboo screen, the middle three layers are all vertical grain, and the rest of the veneer or bamboo screen is laid according to a vertical grain and a horizontal grain. 3. The high-elastic-modulus bamboo-wood composite container bottom plate according to claim 1, characterized in that the longitudinal grain thin bamboo curtain (1) or A longitudinal grain bamboo curtain (2) is covered with a Thin veneer, or phenolic impregnated paper, or phenolic impregnated glass fiber cloth.

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